1. Field of the Invention
The invention relates in general to a printed antenna, and more particularly to a printed antenna used in a wireless network device.
2. Description of the Related Art
Along with the advance in computer and wireless telecommunication technology, wireless area network (WLAN) has been widely used in people's everyday life. Currently, many electronic devices may be connected to a WAN via a wireless network device such as a USB dongle, an access point (AP) or a router.
Conventional wireless network device may receive/transmit wireless signals via an external dipole antenna. Since the external dipole antenna not only jeopardizes the appearance aesthetics of the device but also requires additional purchase cost, the printed antenna formed on the printed circuit board gradually replaces the dipole antenna.
However, the radiation gain and the radiation efficiency of the conventional printed antenna are inferior to that of the dipole antenna, and the bandwidth of the conventional printed antenna is limited to a narrowed range.